Multilayer board

Abstract

A multilayer board includes a thermoplastic resin film layer, a pattern layer layered on the thermoplastic resin film layer, and a conductor pattern. The thermoplastic resin film layer is made of a plurality of thermoplastic resin films layered with each other, and has two adhesive layers and an interlayer located between the two adhesive layers. Each of the adhesive layers has an interlayer connector passing through the adhesive layer in a thickness direction. The conductor pattern is located on at least one of the pattern layer and the interlayer at a position opposing to the interlayer connector.

1 . A multilayer board comprising:
 a thermoplastic resin film layer having a plurality of thermoplastic resin films layered with each other, the thermoplastic resin film being softened at a predetermined temperature;   a pattern layer layered on the thermoplastic resin film layer, the pattern layer having a low-flowability resin film, flowability of the low-flowability resin film being lower than that of the thermoplastic resin film at the predetermined temperature; and   a first conductor pattern having a predetermined thickness, wherein   the thermoplastic resin film layer has a first adhesive layer, a second adhesive layer and an interlayer located between the first and second adhesive layers,   the interlayer has a first interlayer connector passing through the interlayer in a thickness direction,   each of the adhesive layers has a second interlayer connector passing through the adhesive layer in the thickness direction, the second interlayer connector being electrically connected to the first interlayer connector, and   the first conductor pattern is located on at least one of a face of the pattern layer and a face of the interlayer at a position opposing to the second interlayer connector.   
     
     
         2 . The multilayer board according to  claim 1 , wherein
 each of the first interlayer connector and the second interlayer connectors is made of conductive material, the conductive material being defined by filling conductive paste in a via hole, the conductive paste containing metal particles sintered with each other,   the first adhesive layer has a thickness larger than that of the second adhesive layer, and   the first conductor pattern is located on the interlayer, and opposes to the second interlayer connector of the first adhesive layer.   
     
     
         3 . The multilayer board according to  claim 2 , further comprising:
 a second conductor pattern located on the pattern layer, wherein the second conductor pattern opposes to the second interlayer connector of the first adhesive layer.   
     
     
         4 . The multilayer board according to  claim 2 , further comprising:
 a third conductor pattern located on the interlayer, wherein the third conductor pattern opposes to the second interlayer connector of the second adhesive layer.   
     
     
         5 . The multilayer, board according to  claim 1 , further comprising:
 an electronic component located in the interlayer, wherein   the second adhesive layer has an electrode connector electrically connected to an electrode terminal of the electronic component.   
     
     
         6 . The multilayer board according to  claim 1 , further comprising:
 an electronic component located in the interlayer, wherein   each of the first interlayer connector and the second interlayer connectors is made of conductive material, the conductive material being defined by filling conductive paste in a via hole, the conductive paste containing metal particles sintered with each other,   the first adhesive layer has a thickness larger than that of the second adhesive layer,   the second adhesive layer has an electrode connector electrically connected to an electrode terminal of the electronic component, and   the first conductor pattern is located on the interlayer, and opposes to the second interlayer, connector of the first adhesive layer.   
     
     
         7 . The multilayer board according to  claim 6 , further comprising:
 a second conductor pattern located on the pattern layer, wherein the second conductor pattern opposes to the second interlayer connector of the first adhesive layer.   
     
     
         8 . The multilayer board according to  claim 6 , further comprising:
 a third conductor pattern located on the interlayer, wherein the third conductor pattern opposes to the second interlayer connector of the second adhesive layer.   
     
     
         9 . The multilayer board according to  claim 8 , wherein
 the first conductor pattern has a thickness larger than that of the third conductor pattern.   
     
     
         10 . The multilayer board according to  claim 5 , wherein
 the pattern layer has a pad opposing to the electrode connector,   the pad is electrically connected to the electrode connector,   the electrode connector is connected to the electrode terminal of the electronic component, and   the electrode connector is made of a stud bump.   
     
     
         11 . The multilayer board according to  claim 1 , wherein
 the low-flowability resin film is made of a thermosetting resin film.   
     
     
         12 . The multilayer board according to  claim 1 , further comprising:
 an electronic component located in the interlayer, wherein   the interlayer has the conductor pattern opposing to the second interlayer connector of the first adhesive layer and the conductor pattern opposing to the second interlayer connector of the second adhesive layer,   the first interlayer connector is made of conductive material, the conductive material being defined by filling conductive paste in a via hole, the conductive paste containing metal particles sintered with each other,   the interlayer has an inner film and two outer films alternately layered with each other, and   the inner film has elasticity coefficient smaller than that of the outer film at a heating-and-pressing temperature.   
     
     
         13 . The multilayer board according to  claim 12 , wherein
 the elasticity coefficient of the inner film is more than 1.0E+05Pa, and is less than 1.0E+09Pa, at 320° C., and   the elasticity coefficient of the outer film is more than 1.0E+09Pa at 320° C.   
     
     
         14 . The multilayer board according to  claim 12 , wherein
 the inner film has a thickness of t20-500 μm, and   the outer film has a thickness of t12.5-50 μm.   
     
     
         15 . The multilayer board according to  claim 1 , wherein
 the pattern layer has a plurality of pattern films and an adhesive film located between the pattern films, a face of the pattern film having another conductor pattern made of copper foil,   the pattern film is made of the low-flowability resin film,   each of the pattern film and the adhesive film has a third interlayer connector that electrically connects the conductor, patterns with each other, the third interlayer connector passing through the film in the thickness direction,   the third interlayer connector is made of conductive material, the conductive material being defined by filling conductive paste in a via hole, the conductive paste containing metal particles sintered with each other, and   the adhesive film has elasticity coefficient smaller than that of the pattern film at a heating-and-pressing temperature.   
     
     
         16 . The multilayer board according to  claim 15 , wherein
 the elasticity coefficient of the adhesive film is more than 1.0E+05Pa, and is less than 1.0E+08Pa, at 320° C., and   the elasticity coefficient of the pattern film is more than 1.0E+09Pa at 320° C.   
     
     
         17 . The multilayer board according to  claim 15 , wherein
 the adhesive film has a thickness of t20-300 μm, and   the pattern film has a thickness of t12.5-50 μm.